Analysis And Risk Assessment Of Atmospheric Dust Sources In Ningdong Yangchangwan Mining Area And Its Surrounding

The Coal base of Ningdong is a typical mining city,and the Yangchangwan mining area of Ningdong is a large scale well working mine in its interior.From Yangchangwan mine No.1 to No.5,many long-running well working coal mines and the derived industrial activities lead to increasingly serious air pollution.Bay in ningdong sheep field mining area as the research object,with dust cylinders,weather stations and other instruments of ningdong sheep field bay mining area and the surrounding atmospheric dust and meteorological data in field,the fixed location monitoring of the microwave digestion instrument and ICP,computer is used to measure the atmospheric dust heavy metal content,using the correlation analysis,factor analysis and other analysis method and risk evaluation model of spatial and temporal variations of atmospheric heavy,source and the ecology and human health risk evaluation,which provides the theoretical support for improving ecological security in the study area.(1)Atmospheric dust content in yangchangwan Mining area and surrounding areas of Ning Dong varies greatly in different periods and different functional areas.The overall dust content rises first and then decreases.In April,the dust content is 66.54t/km2·30d,which is the month with the highest dust content;in November,the dust content is 8.43 t /km2·30d,which is the month with the lowest dust content.In addition,different seasons,heating season and non-heating season,wind season and non-wind season dust precipitation is also different.(2)the order of the annual average content of heavy metal elements in atmospheric precipitation in yongyangchang bay mining area is: Fe > Al > Ti > Zn > Mg > As > Ba > Mn > Cr > Pb > V >Ni >Sb >Cu > Li >Co >Cd >Be,in which Fe content is the largest and Be content is the smallest.The content difference between different elements is obvious,and the human disturbance is different.(3)By enrichment factor analysis,correlation analysis,factor analysis,multiple linear regression analysis,the research in atmospheric dust source there are 7 classes,the main coal mining and transport diffusion respectively,metallurgical dust and fuel dust,traffic dust,soil dust,coal dust,coal washing process producing dust,accounted for 17.55%,13.66%,13.53%,11.52%,11.25%,10.03% and 6.26%.(4)According to the analysis of the potential ecological hazard index method,the potential ecological risk factors of Cd and As in the study area are at a very high risk,the potential ecological risk factors of Pb and Zn are at a low risk,and the total potential ecological hazard index of heavy metals is at a very high risk.Among them,Cd and As contributed significantly,70.58% and 26.52% respectively.(5)According to the health risk assessment,the total non-carcinogenic risk of children and adults in and around the Yangchangwan mine area in Ningdong is greater than 1,and there is a non-carcinogenic risk,exceeding the safety threshold of not causing harmful effects on the health of the contacts.As,Cr,Ni,Co and Cd all have the risk of cancer,with As being the highest and Cd the lowest.The carcinogenic risks of the three ingestion pathways were ranked as follows: the hand-mouth ingestion pathway >;the skin-contact pathway >;the respiratory inhalation pathway.